[Keith] wanted to use his makerbot for some PCB milling, but he ran into a pretty big problem. The platform that his PCB would sit on was mounted with a layer of double sided foam tape and was not perfectly aligned to the head. Not only that, but it would tilt when pressure was applied. This made the result of the milling completely unacceptable. To remedy this, he made a new platform that is not only rigid, but he has made it so that there is the ability to adjust it for perfect alignment via adjustment screws in the 4 corners. At the beginning of each session, he can be absolutely sure that everything is aligned perfectly and his PCBs show a huge improvement. You can see a comparison of the two in the following picture.